Device for producing offset prints



Patented Sept. 27, 1927.

01 BERLIN, GEBIANY.

DEVICE FOR PRODUCING OFFSET PRINTS.

Application fled lebruary 14, 1985, Serial No. 8,270, and in GermanyFebruary 23, 1924.

My invention relates to a cylinder printing machine on which two-colouroffset printing, or two-colour book and offset printing, or one colourbook, or one colour 6 offset printing, can be produced, andon over orreverse this right-sided proof by pressing it onto a suitable transfermaterial.

and from this material I transfer the print right side up to the zinc'or aluminum plate to be mounted on the plate cylinder of .a printingpress. After the usual pre aration of this plate printing can be proceeed with at once and a one-colour offset print is ob-.'

tained in this manner.

If plates are to be prepared for twocolour offset printing, two proofsare made, for instance from the type or printing forme of a printingress. The first proo which shall be trans erred as the first colour, isthen covered over on those portions, which shall be printed in thesecond colour, while on the second proof which shall be reprinted in thesecond colour, all those portions are covered over, which serve to printthe first colour. Thefirst proof bein covered over as described is nowturne over or reversed on a suitable transfer material. The same is donewith the second colour proof on another transfer material. From each ofthese materials a right slde up proof is made on a separate zinc oraluminum.

plate and the plates, being prepared in a well-known manner, are thenmounted on the res ctive late c linder. 4 5, P

viding plates for single or multicolour offset rinting I refer using aprinting machine 1y means 0 which not only this process can be carriedout in a ver sim le manner, but

plates in the manner aforesaid.

In ractical o ration the rinti lates p p6 P ng p A with the cylinder 12.(l is the bedplate and are 0 tained in the following manner:

sheet of paper is fixed on theprintmg cylinder of an offset printingpress, preferabl of the novel-type which will be descri practising t isnovel method of prowhich will also serve or printing from the molespecifically hereinafter, and I operate this press so as to produce aprint on the sheet from the printing forme. The right side up proof thusobtained is directly transferred onto the rubber cylinder of the offsetrinting press in right to left reversal and is reproduced right side upon the printing plate contacting with the rubber cylinder.

Instead of transferring the right side up proof first obtained onto therubber cylinder, 1 may also replace the. printing forme from which thisproof has been taken, by a rubber plate, onto which this proof is thentransferred by causing the rubber plate to move in contact with theproof lying on the printing cylinder, and from this rubber plate theright to left print is then transferred right side up onto a printingplate mounted onto a plate cylinder adapted to rotate in contact withthe rubber plate.

The printing press which allows practising the novel process, and whichis preferably of the cylinder high speed press type, has mounted againstthe impression cylinder a transfer member, preferably the well knownrubber cylinder, which is adapted to.

transfer fom the impression cylinder onto the late cylinder and viceversa'. There is furt er provided a rubber plate adapted to reciprocatebelow and in contact with the impression cylinder, and this rubber platecan be replaced by a printin forme. Above the rubber plate is mounte asecond plate cylinder, both this and the rubber cylinder are adapted tobe thrown out of operation separately. The operator is at leisure to usein the transferring of the proof onto a printing plate either the rubbercylinder or the rubber plate or both of them. 7

In the drawings afiixed to this specification and forming part thereof,a device embodying my invention is illustrated diagrammatical y by wayof example.

In the drawings Fig. 1 is an elevation partly in vertical section of acylinder printing machine embodying my invention, while Fig. 2illustrates a detail.

Referring to the drawings, ais the impression cylinder, 12 the rubber clinder mounted to run against it, and a t e zinc late or similarcylinder which cooperates the rubber surface .removably arran d thereon,and e is the zincplate or sim ar ,cylinder mounted above the bedplate.

- this invention in the following manner:

As shown in Fig. 2 plate cylinder 0 has its journals 0 mounted in aneccentric e arranged for rotation in bearings and carrying an arm e thefree end of which is connected with a hand lever e by means of a link e.A bar 6 extends between the points of connection of the arms (2 andlinks e on either side of the machine thereby allowing the eccentrics eon either side of the plate c linder e to be turned by means of a singleandle e. A similar arrangement is providedfor throwing out platecylinder 0 and rubber cylinder .6.

The necessary transfers on the plate cylinders c and e forthepreparation of the oifset printing, are obtained according to After thetype or printing forme has been arranged in the proper size, and withthe proper registration, for example on the bedplate (2, a proof istaken therefrom-on a suitable paper which is fixedon the impressioncylinder a. This proof is a positive or right-sided one. By simplyallowing it to pass through the machine, the right-sided proof is turnedover or reversed on the rubber cylinder 6 and transferred therefromright side up to the plate of the plate cylinder a, After the usualpreparation of the plate and after the type forme at (Z has been removedthe printing can be effected at once by means of the cylinders 0, b, a,a one-colour ofi'set print being thus obtaine If plates are to be madefor use in twocolour offset printing, two proofs are made from the typeor printing forme. The first proof which shall be transferred as thefirst colour is covered over on those portions which shall be printed inthe second colour while conversely, on the secondproof, which shall beprinted in the second colour, those portions are'covered over whichserve to print the first colour. The first proof is now transferred inthe manner just described onto the plate cylinder 0, while the secondproof, after the substitution of the type forme on the bed plate at bythe rubber surface, is

transferred to the plate ofthe plate cylinder e by simply allowing it torun through the machine rear side upwards onto the rubber plate, fromwhich it passes right side up onto the plate cylinder e. After theplates have thus been prepared and finished, printing may commence atonce.

Printing is now proceeded with in the following manner, assumingtwo-colour work printing on one side to be produced:

The sheet which is seized in the usual manner by the grippers (notshown) of the impression cylinder a is printed in its first colour bythe rubber cylinder 1) andin its second colour on its passage betweenthe impression cylinder at and the bedplate d by the rubber surfacemounted on this latter 1 and which has received the proof orofi'set Einto contact with the plate cylinder e. If on v the other hand thecylinder e be thrown out of operation, simple offset printing can beproduced by means of the cylinders b and 0,

in which case the machine is preferably run more rapidl In like mannerthe machine can be use as a simple high speed book printing press afterthe offset printing mechanism 0, b and the c linder e have been put outof operation an an ordinary book printing forme inserted in the bedplated.

In this way a very accurate registration of the plates in two-colouroffset printing,

and an extremely rapid reproduction of the printing plates for offsetprinting, is en-. sured, without any other auxiliary machines beingrequired.

I wish it to be understood that I do not desire to be limited to theexact details of construction shown and described, forobviousmodifications will occur to a person skilled in the art.

I claim:

1. Cylinder printing machine comprising a frame, an impression cylinderrotatably supported in said frame, a plate cylin der and a rubber,cylinder rotatably supported in said frame, said rubber cylinder beinginserted between said impression cylinder and said plate cylinder andadapted to transfer one colour from said plate cylinder onto saidimpression cylinder, a rubber plate mounted for, reciprocation andcontacting with said impression cylinder and means for depositinganother colour a frame, an impression cylinder rotatably supported insaid frame, a late cylinder and arubber cylinder rotata 1y supported insaid frame, said rubber cylinder being inserted between said. impressioncylinder and said plate cylinder and adapted to transfor one colour fromsaid plate cylinder onto said impression cylinder, -'a rubber platemounted for reciprocation-and contacting .transfer one colour der ontosaid lmpression cyllnder,

. thrown out.

a rubber cylinder rotata ly supported with said impression cylinder anda second plate cylinder for depositing another colour on said rubberplate. a

4. Cylinder printing-machine comprising a frame, an impression cylinderrotatably supported in said frame, a late cylinder and a rubber cylinderrotata ly supported in said frame, said rubber cylinder. being insertedbetween said impression cylinder and said plate cylinder and adapted tofrom said plate cylina rubber plate mounted for reciprocation andcontacting with said impression cylinder and, a second plate cylinderfor depositin another colour on said rubber plate sai second platecylinder being arranged to be machine comprising cylinder rotatably alate cylinder and in 5. Cylinder printing a frame, an impressionsupported in said frame,

' said frame, said rubber cylinder being insupported in said frame, a

serted between said impression cylinder and said plate cylinder andadapted to transfer one colour from said plate cylinder onto saidimpression cylinder, a rubber plateremovably mounted for reciprocationand contact-, ing with said impression cylinder and a second platecylinder for depositing another colour on said rubber plate, said secondplate cylinder being arranged to be thrown out;

6. Cylinder printing machine comprising a frame, an impression cylinderrotatably late cylinder and a rubber cylinder rotata 1 supported in saidframe, said rubber cy inder being inserted between said impressioncylinder and said plate cylinder and adapted totransfer one colour fromsaid plate cylinder onto said impression cylinder, said rubber cylinderbeing arranged to be thrown out, a rubber plate mounted forreciprocation and contacting with said impression cylinder and means fordepositing another colour on said rubber plate.

7. Cylinder printing machine comprising a frame, an impression cylinderrotatably supported in said frame, a' late cylinder and a rubbercylinder rotata ly supported in said frame, said rubber cylinder beinginserted between said impression cylinder and said'plate cylinder andadapted to trans fer the one from said plate cylinder onto saidimpression cylinder, a rubber plate mounted for reciprocation andcontactin with said impression cylinder and,'a second plate cylinder fordepositing another colour on said rubber plate said rubber cylinder andsaid second plate cylinder being arranged to be thrown out.

8. Cylinder printing machine comprising a frame, a plate cylinder and arubber cylinder rotatably supported in said frame, said rubber cylinderbeing inserted between said impression c linder and said plate cylinderand adapte to transfer one colour from said plate cylinder onto saidimpression cylinder, a rubber plate removably mounted forlreci 'rocatingand contacting with a sheet lying on said impression cylinder, and asecond plate cylinder for depositing another colour on said rubberplate, said rubber cylinder and said second plate cylinder beingarranged to be thrown out.

In testimony whereof I affix my si HERMAN BIELEFE ature. DT.

